Field of the Invention
The present invention relates to an information-processing apparatus and an information-processing method.
Description of the Related Art
For the purpose of enabling immediate, intuitive grasp of a brightness distribution of image data, a waveform monitor apparatus is generally used. In a waveform monitor apparatus, a two-dimensional histogram of image data is acquired and a waveform is displayed in the manner of an oscilloscope (see Japanese Patent Application Publication No. H7-38801). Moreover, a digital oscilloscope capable of performing variable-density display of a waveform is also available. As a technique related to such a digital oscilloscope, a technique of normalizing the distribution of data values of input data so that a density distribution of a waveform is easily observed has been proposed (Japanese Patent Application Publication No. 2008-122423).
In photographing, the gradation characteristics γ2.2 to γ2.6 which are standards stipulated by ITU-R Rec.BT.709, DCI, etc., are often used as an optical-electro transfer function (OETF). In photographing, the optical-electro transfer function is a characteristic for converting a brightness-related value (a value related to brightness), obtained by sensors, to a data value of image data. Meanwhile, the characteristic for converting a data value to a display brightness-related value is referred to as an “electro-optical transfer function (EOTF)”. The gradation characteristic is a correspondence relation between the brightness-related value and the data value.
Currently, the use of new gradation characteristics as exemplified by SMPTE ST2084, ARIB STD-B67, etc., is becoming increasingly widespread. Such a new gradation characteristic is used as the EOTF of an image display apparatus capable of displaying images in a high dynamic range (HDR), for example. The HDR is a wider dynamic range than a general dynamic range (standard dynamic range: SDR). HDR supports a high brightness that SDR does not support.
However, in a case where the conventional waveform monitor apparatus described above is used, users cannot easily have an accurate grasp of a brightness distribution of image data having nonlinear EOTF as exemplified by SMPTE ST2084, ARIB STD-B67, etc. More specifically, it is difficult for users to have an acute sense for contrasts in a high brightness range. This is because in such a high brightness range of EOTF, the inclination of the change in the brightness-related value in relation to the change in the data value is very steep.
Although there is an increasing demand for simultaneously using a plurality of different EOTFs, in a case where the conventional waveform monitor is used, it is not easy for users to accurately compare a plurality of brightness distributions corresponding to the plurality of EOTFs.